The Anglo Belgian Corporation ( ABC ) is a Belgian manufacturer of medium speed diesel engines, primarily for the marine market, as well as stationary and locomotive markets.
87-592: 30CC and 40CC (starting): 519 kN (117,000 lbf) @ μ = 0.33 The Voith Maxima locomotives are a family of diesel-hydraulic locomotives built by Voith Turbo Lokomotivtechnik GmbH & Co. KG. , a subsidiary of Voith . Initially, two versions of a 6-axle C'C' machine were offered with medium speed engines from the Anglo-Belgian Corporation : the Maxima 30CC and Maxima 40CC (the most powerful single-engined diesel-hydraulic locomotive in
174-523: A contract to operate the Marschbahn from December 2005, and contracted Vossloh to build new locomotives ("R3000 CC") to operate it; the locomotive's design specifications were a top speed of 160 km/h (99 mph) and power of over 3 MW. Initially the service was to be operated by the MaK DE 2700 type, before the new 'R3000' locomotives were built. The LS 640 reU2 transmission (input power 4.2 MW.)
261-645: A graphene sheet in the presence of graphene-adsorbed oxygen. Despite being a simplified model of friction, the Coulomb model is useful in many numerical simulation applications such as multibody systems and granular material . Even its most simple expression encapsulates the fundamental effects of sticking and sliding which are required in many applied cases, although specific algorithms have to be designed in order to efficiently numerically integrate mechanical systems with Coulomb friction and bilateral or unilateral contact. Some quite nonlinear effects , such as
348-411: A new surface forms at the back of a sliding true contact, and existing surface disappears at the front of it. Since all surfaces involve the thermodynamic surface energy, work must be spent in creating the new surface, and energy is released as heat in removing the surface. Thus, a force is required to move the back of the contact, and frictional heat is released at the front. For certain applications, it
435-400: A parameter describing the scaling behavior of surface asperities, is known to play an important role in determining the magnitude of the static friction. For surfaces in relative motion μ = μ k {\displaystyle \mu =\mu _{\mathrm {k} }} , where μ k {\displaystyle \mu _{\mathrm {k} }} is
522-602: A result Vossloh abandoned the 'R3000' development, instead offering the Vossloh Euro and Vossloh G2000 designs for mainline work. The Euro 4000 was offered to the Marschbahn instead of the 'R3000'. Because it lost an outlet for its new transmission, Voith began development of a new high-powered mainline locomotive - the Voith Maxima. Voith then developed in house new high-powered diesel locomotive series along with single cab shunting and trip freight locomotives,
609-472: A rough body driven over a rough surface, the mechanical work done by the driver exceeds the mechanical work received by the surface. The lost work is accounted for by heat generated by friction. Over the years, for example in his 1879 thesis, but particularly in 1926, Planck advocated regarding the generation of heat by rubbing as the most specific way to define heat, and the prime example of an irreversible thermodynamic process. The focus of research during
696-515: A single study has demonstrated the potential for an effectively negative coefficient of friction in the low-load regime , meaning that a decrease in normal force leads to an increase in friction. This contradicts everyday experience in which an increase in normal force leads to an increase in friction. This was reported in the journal Nature in October 2012 and involved the friction encountered by an atomic force microscope stylus when dragged across
783-419: A threshold value for this force, above which motion would commence. This maximum force is known as traction . The force of friction is always exerted in a direction that opposes movement (for kinetic friction) or potential movement (for static friction) between the two surfaces. For example, a curling stone sliding along the ice experiences a kinetic force slowing it down. For an example of potential movement,
870-434: A very poor approximation (for example, adhesive tape resists sliding even when there is no normal force, or a negative normal force). In this case, the frictional force may depend strongly on the area of contact. Some drag racing tires are adhesive for this reason. However, despite the complexity of the fundamental physics behind friction, the relationships are accurate enough to be useful in many applications. As of 2012 ,
957-409: Is (highly ordered pyrolytic) graphite which can have a friction coefficient below 0.01. This ultralow-friction regime is called superlubricity . Static friction is friction between two or more solid objects that are not moving relative to each other. For example, static friction can prevent an object from sliding down a sloped surface. The coefficient of static friction, typically denoted as μ s ,
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#17327942779501044-648: Is 80 m (260 ft). The locomotive can take up to 9,000 or 10,000 L (2,000 or 2,200 imp gal; 2,400 or 2,600 US gal) of fuel, depending on the configuration. The locomotives are assembled at a new plant next to the Nord-Ostsee-Kanal in Kiel. Large maintenance and overhauls will be carried out in a new central workshop in Cologne, to be operated jointly by Voith Turbo and HGK . Voith initially offered two variants of this locomotive:
1131-498: Is a dimensionless scalar value which equals the ratio of the force of friction between two bodies and the force pressing them together, either during or at the onset of slipping. The coefficient of friction depends on the materials used; for example, ice on steel has a low coefficient of friction, while rubber on pavement has a high coefficient of friction. Coefficients of friction range from near zero to greater than one. The coefficient of friction between two surfaces of similar metals
1218-408: Is an empirical measurement — it has to be measured experimentally , and cannot be found through calculations. Rougher surfaces tend to have higher effective values. Both static and kinetic coefficients of friction depend on the pair of surfaces in contact; for a given pair of surfaces, the coefficient of static friction is usually larger than that of kinetic friction; in some sets
1305-495: Is an approximate model used to calculate the force of dry friction. It is governed by the model: F f ≤ μ F n , {\displaystyle F_{\mathrm {f} }\leq \mu F_{\mathrm {n} },} where The Coulomb friction F f {\displaystyle F_{\mathrm {f} }} may take any value from zero up to μ F n {\displaystyle \mu F_{\mathrm {n} }} , and
1392-437: Is greater than that between two surfaces of different metals; for example, brass has a higher coefficient of friction when moved against brass, but less if moved against steel or aluminum. For surfaces at rest relative to each other, μ = μ s {\displaystyle \mu =\mu _{\mathrm {s} }} , where μ s {\displaystyle \mu _{\mathrm {s} }}
1479-424: Is impending, is sometimes referred to as limiting friction , although this term is not used universally. Kinetic friction , also known as dynamic friction or sliding friction , occurs when two objects are moving relative to each other and rub together (like a sled on the ground). The coefficient of kinetic friction is typically denoted as μ k , and is usually less than the coefficient of static friction for
1566-415: Is maintained that μ is always < 1, but this is not true. While in most relevant applications μ < 1, a value above 1 merely implies that the force required to slide an object along the surface is greater than the normal force of the surface on the object. For example, silicone rubber or acrylic rubber -coated surfaces have a coefficient of friction that can be substantially larger than 1. While it
1653-562: Is more useful to define static friction in terms of the maximum angle before which one of the items will begin sliding. This is called the angle of friction or friction angle . It is defined as: tan θ = μ s {\displaystyle \tan {\theta }=\mu _{\mathrm {s} }} and thus: θ = arctan μ s {\displaystyle \theta =\arctan {\mu _{\mathrm {s} }}} where θ {\displaystyle \theta }
1740-479: Is no sliding occurring, the friction force can have any value from zero up to F max {\displaystyle F_{\text{max}}} . Any force smaller than F max {\displaystyle F_{\text{max}}} attempting to slide one surface over the other is opposed by a frictional force of equal magnitude and opposite direction. Any force larger than F max {\displaystyle F_{\text{max}}} overcomes
1827-456: Is often stated that the COF is a "material property," it is better categorized as a "system property." Unlike true material properties (such as conductivity, dielectric constant, yield strength), the COF for any two materials depends on system variables like temperature , velocity , atmosphere and also what are now popularly described as aging and deaging times; as well as on geometric properties of
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#17327942779501914-434: Is on a level surface and subjected to an external force P {\displaystyle P} tending to cause it to slide, then the normal force between the object and the surface is just N = m g + P y {\displaystyle N=mg+P_{y}} , where m g {\displaystyle mg} is the block's weight and P y {\displaystyle P_{y}}
2001-423: Is perpendicular to the surfaces. In the simple case of a mass resting on a horizontal surface, the only component of the normal force is the force due to gravity, where N = m g {\displaystyle N=mg\,} . In this case, conditions of equilibrium tell us that the magnitude of the friction force is zero , F f = 0 {\displaystyle F_{f}=0} . In fact,
2088-409: Is proportional to the normal force (until saturation, which takes place when all area is in atomic contact); and that the frictional force is proportional to the applied normal force, independently of the contact area. The Coulomb approximation is fundamentally an empirical construct. It is a rule-of-thumb describing the approximate outcome of an extremely complicated physical interaction. The strength of
2175-573: Is responsible for the Coulomb damping of an oscillating or vibrating system. New models are beginning to show how kinetic friction can be greater than static friction. In many other cases roughness effects are dominant, for example in rubber to road friction. Surface roughness and contact area affect kinetic friction for micro- and nano-scale objects where surface area forces dominate inertial forces. The origin of kinetic friction at nanoscale can be rationalized by an energy model. During sliding,
2262-466: Is the coefficient of static friction . This is usually larger than its kinetic counterpart. The coefficient of static friction exhibited by a pair of contacting surfaces depends upon the combined effects of material deformation characteristics and surface roughness , both of which have their origins in the chemical bonding between atoms in each of the bulk materials and between the material surfaces and any adsorbed material . The fractality of surfaces,
2349-412: Is the angle from horizontal and μ s is the static coefficient of friction between the objects. This formula can also be used to calculate μ s from empirical measurements of the friction angle. Determining the forces required to move atoms past each other is a challenge in designing nanomachines . In 2008 scientists for the first time were able to move a single atom across a surface, and measure
2436-497: Is the downward component of the external force. Prior to sliding, this friction force is F f = − P x {\displaystyle F_{f}=-P_{x}} , where P x {\displaystyle P_{x}} is the horizontal component of the external force. Thus, F f ≤ μ N {\displaystyle F_{f}\leq \mu N} in general. Sliding commences only after this frictional force reaches
2523-471: Is transformed to heat as well as the free energy of the structural changes and other types of dissipation , so mechanical energy is not conserved. The complexity of the interactions involved makes the calculation of friction from first principles difficult and it is often easier to use empirical methods for analysis and the development of theory. There are several types of friction: Many ancient authors including Aristotle , Vitruvius , and Pliny
2610-537: Is usually higher than the coefficient of kinetic friction. Static friction is considered to arise as the result of surface roughness features across multiple length scales at solid surfaces. These features, known as asperities are present down to nano-scale dimensions and result in true solid to solid contact existing only at a limited number of points accounting for only a fraction of the apparent or nominal contact area. The linearity between applied load and true contact area, arising from asperity deformation, gives rise to
2697-571: The Belgian Congo , which had become independent in 1960 and could not afford new engines. In 1973, the license for the manufacture of high-speed engines was obtained from SEMT Pielstick ; additionally the company developed an entirely new engine codenamed DZC operating at 1000 rpm. By 1979 the company needed capital, negotiations with private investors failed, and the company went bankrupt. The company restarted under new management and with new investors (the companies Pauwels , Batibo , and
Voith Maxima - Misplaced Pages Continue
2784-539: The Belgian Railways Class 77 and Voith Maxima ), as well as dual fuel (gas/oil) DZD engines. The DL and DV36 range are large-bore (365mm) series with outputs between 3900 and 10400 kW. These are intended for larger ships and oversized powerplants. The hydrogen internal combustion engines, made by BeHydro (see above) are used in the HydroTug. The EL23, a multi-fuel model, is the newest engine in
2871-602: The Belgian Shipbuilding Corporation as well as with government investment) and was renamed Anglo Belgian Corporation . Problems with production versions of the DZC engine required further investment to fix, and the shareholders lost confidence in the company, refusing an increase in capital. As a result, they passed their shares to Ogepar , a Luxembourg-based holding company, thereby raising 75,000,000 Belgian francs in capital. The modified DZC engine
2958-537: The Voith Gravita series. With a development period of just 500 days, the first locomotive was ready in 2006 and presented at the InnoTrans 2006 fair. The locomotive design won a red dot design award in 2007. A new factory in Kiel was established in 2006 by Voith to manufacture the new locomotives. At Innotrans in 2008, Voith added a third potential model to its Maxima range, the 4 axle Maxima 20BB. The type
3045-860: The atomic scale , showing that, on that scale, dry friction is the product of the inter-surface shear stress and the contact area. These two discoveries explain Amonton's first law (below) ; the macroscopic proportionality between normal force and static frictional force between dry surfaces. The elementary property of sliding (kinetic) friction were discovered by experiment in the 15th to 18th centuries and were expressed as three empirical laws: Dry friction resists relative lateral motion of two solid surfaces in contact. The two regimes of dry friction are 'static friction' (" stiction ") between non-moving surfaces, and kinetic friction (sometimes called sliding friction or dynamic friction) between moving surfaces. Coulomb friction, named after Charles-Augustin de Coulomb ,
3132-400: The coefficient of kinetic friction . The Coulomb friction is equal to F f {\displaystyle F_{\mathrm {f} }} , and the frictional force on each surface is exerted in the direction opposite to its motion relative to the other surface. Arthur Morin introduced the term and demonstrated the utility of the coefficient of friction. The coefficient of friction
3219-588: The movie Archived 2015-01-10 at the Wayback Machine for more details. Anglo-Belgian Corporation On 26 October 1912 the Anglo Belgian corporation was founded; the company was to manufacture the new semi-diesel engines . One of the investors was the Onghena company, a manufacturer of gas engines, which would contribute part of their factory space and machinery towards the production of
3306-404: The 'song' of a glass harp , phenomena which involve stick and slip, modelled as a drop of friction coefficient with velocity. A practically important case is the self-oscillation of the strings of bowed instruments such as the violin , cello , hurdy-gurdy , erhu , etc. A connection between dry friction and flutter instability in a simple mechanical system has been discovered, watch
3393-647: The 1930s - in particular its hydraulic transmissions . Merger of the Deutsche Reichsbahn and Deutsche Bundesbahn in the 1994 resulted in the German state railways acquiring many high-powered diesel locomotives of the DR Class 130 family , which reduced any opportunities for sale of a high power transmission to the Deutsche Bahn in the medium term. However, in 2004 Nord-Ostsee-Bahn acquired
3480-435: The 20th century has been to understand the physical mechanisms behind friction. Frank Philip Bowden and David Tabor (1950) showed that, at a microscopic level , the actual area of contact between surfaces is a very small fraction of the apparent area. This actual area of contact, caused by asperities increases with pressure. The development of the atomic force microscope (ca. 1986) enabled scientists to study friction at
3567-664: The Elder , were interested in the cause and mitigation of friction. They were aware of differences between static and kinetic friction with Themistius stating in 350 A.D. that "it is easier to further the motion of a moving body than to move a body at rest". The classic laws of sliding friction were discovered by Leonardo da Vinci in 1493, a pioneer in tribology , but the laws documented in his notebooks were not published and remained unknown. These laws were rediscovered by Guillaume Amontons in 1699 and became known as Amonton's three laws of dry friction. Amontons presented
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3654-608: The Maxima 20BB was added to the range in 2007. Voith signed an exclusive contract with Saxon model building company Sächsische Waggonfabrik Stollberg to build a H0 -model of both Maxima variants. All parts of the locomotive will be engineered and made in Germany. Coefficient of friction Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of
3741-406: The approximation is its simplicity and versatility. Though the relationship between normal force and frictional force is not exactly linear (and so the frictional force is not entirely independent of the contact area of the surfaces), the Coulomb approximation is an adequate representation of friction for the analysis of many physical systems. When the surfaces are conjoined, Coulomb friction becomes
3828-435: The classic empirical model of friction (static, kinetic, and fluid) commonly used today in engineering. In 1877, Fleeming Jenkin and J. A. Ewing investigated the continuity between static and kinetic friction. In 1907, G.H. Bryan published an investigation of the foundations of thermodynamics, Thermodynamics: an Introductory Treatise dealing mainly with First Principles and their Direct Applications . He noted that for
3915-604: The company produces 6- and 8-cylinder DL36 engines in power ranges from 3950 to 5200 kW, inline 6- and 8-cylinder DZ engines from 864 to 1768 kW, and 12- and 16-cylinder V engines (V-DZC) of rated power either 2650 kW or 3536 kW. The engines are found on large river barges such as those found on the Rhine , coastal freighters, fishing boats, ferries, tugboats (which typically use two engines), and other ships. Other applications include electricity generation, pumping engines, engines for cranes, and also locomotives (including
4002-598: The company. Since the launch of this engine, over 1200 units have been produced at the Ghent factory, for various applications. Over time, the VDZC's product range grew to include larger turnkey projects. The largest of these arose in 2009 in Brazzaville, Congo, where a standalone power plant was built with ten 16VDZC engines, generating a total of 32MW of electrical power. In January 2011, Tim Berckmoes, who had been working at
4089-501: The contacting materials, such as surface roughness. The coefficient of friction is not a function of mass or volume. For instance, a large aluminum block has the same coefficient of friction as a small aluminum block. However, the magnitude of the friction force itself depends on the normal force, and hence on the mass of the block. Depending on the situation, the calculation of the normal force N {\displaystyle N} might include forces other than gravity. If an object
4176-433: The direction of the frictional force against a surface is opposite to the motion that surface would experience in the absence of friction. Thus, in the static case, the frictional force is exactly what it must be in order to prevent motion between the surfaces; it balances the net force tending to cause such motion. In this case, rather than providing an estimate of the actual frictional force, the Coulomb approximation provides
4263-433: The drive wheels of an accelerating car experience a frictional force pointing forward; if they did not, the wheels would spin, and the rubber would slide backwards along the pavement. Note that it is not the direction of movement of the vehicle they oppose, it is the direction of (potential) sliding between tire and road. The normal force is defined as the net force compressing two parallel surfaces together, and its direction
4350-412: The equivalent non-turbocharged version were made, as were naturally aspirated versions, including turbocharged and intercooled versions. The company was prosperous up to the 1970s, and its engines were used in ships, locomotives (usually of the shunting type) and for electricity generation. During the 1970s the company's financial situation became unfavourable, exacerbated by the loss of one major market,
4437-459: The extent of the surface area; the normal pressure (or load); and the length of time that the surfaces remained in contact (time of repose). Coulomb further considered the influence of sliding velocity, temperature and humidity, in order to decide between the different explanations on the nature of friction that had been proposed. The distinction between static and dynamic friction is made in Coulomb's friction law (see below), although this distinction
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#17327942779504524-626: The firm since 1999, was appointed as General Manager. In order to extend the existing product range, ABC designed a new engine. ABC's engineering department, together with the Austrian engineering company AVL, worked intensively on this project. A new production and assembly facility was launched at the beginning of 2011. A new 5,000 m building was completed in 2012. The facility included late-model tooling machines, equipment and test-benches, along with assembly robots. Since then, ABC has been awarded numerous new projects for large customers around
4611-556: The force of gravity is perpendicular to the face of the plane. The normal force and the frictional force are ultimately determined using vector analysis, usually via a free body diagram . In general, process for solving any statics problem with friction is to treat contacting surfaces tentatively as immovable so that the corresponding tangential reaction force between them can be calculated. If this frictional reaction force satisfies F f ≤ μ N {\displaystyle F_{f}\leq \mu N} , then
4698-406: The force of static friction and causes sliding to occur. The instant sliding occurs, static friction is no longer applicable—the friction between the two surfaces is then called kinetic friction. However, an apparent static friction can be observed even in the case when the true static friction is zero. An example of static friction is the force that prevents a car wheel from slipping as it rolls on
4785-402: The forces required. Using ultrahigh vacuum and nearly zero temperature (5 K), a modified atomic force microscope was used to drag a cobalt atom, and a carbon monoxide molecule, across surfaces of copper and platinum . The Coulomb approximation follows from the assumptions that: surfaces are in atomically close contact only over a small fraction of their overall area; that this contact area
4872-489: The friction force always satisfies F f ≤ μ N {\displaystyle F_{f}\leq \mu N} , with equality reached only at a critical ramp angle (given by tan − 1 μ {\displaystyle \tan ^{-1}\mu } ) that is steep enough to initiate sliding. The friction coefficient is an empirical (experimentally measured) structural property that depends only on various aspects of
4959-486: The frictional heating is removed rapidly, the temperature drops, the pin remains solid and the COF rises to that of a 'low speed' test. In systems with significant non-uniform stress fields, because local slip occurs before the system slides, the macroscopic coefficient of static friction depends on the applied load, system size, or shape; Amontons' law is not satisfied macroscopically. Under certain conditions some materials have very low friction coefficients. An example
5046-592: The globe. Examples include backup diesel generators for nuclear power plants at the French utility EDF, as well as diesel engines for various navies, dredging companies, mining companies, port authorities, tugboat firms, and passenger ferries. In 2019, ABC was awarded the Trends Gazelle Award for the fastest-growing export company in Belgium in its category. In 2019, a joint venture between ABC and CMB
5133-441: The ground. Even though the wheel is in motion, the patch of the tire in contact with the ground is stationary relative to the ground, so it is static rather than kinetic friction. Upon slipping, the wheel friction changes to kinetic friction. An anti-lock braking system operates on the principle of allowing a locked wheel to resume rotating so that the car maintains static friction. The maximum value of static friction, when motion
5220-457: The inclined plane of successive asperities , then why is it not balanced through descending the opposite slope? Leslie was equally skeptical about the role of adhesion proposed by Desaguliers, which should on the whole have the same tendency to accelerate as to retard the motion. In Leslie's view, friction should be seen as a time-dependent process of flattening, pressing down asperities, which creates new obstacles in what were cavities before. In
5307-411: The interface between the materials, namely surface structure . For example, a copper pin sliding against a thick copper plate can have a COF that varies from 0.6 at low speeds (metal sliding against metal) to below 0.2 at high speeds when the copper surface begins to melt due to frictional heating. The latter speed, of course, does not determine the COF uniquely; if the pin diameter is increased so that
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#17327942779505394-637: The interwar period the company obtained a license from Paxman Ricardo for the production of 1500 rpm engines. During the Second World War, production continued at a reduced level. Also, during this period, prototypes for a medium-speed four-stroke single-acting engine were produced, codenamed DU (diesel universal). In the decades after the Second World War, the DU engine was developed and modified: 5-, 6- and 8-cylinder versions were produced, turbocharged versions (codenamed DUX) with 50% more power than
5481-530: The linearity between static frictional force and normal force, found for typical Amonton–Coulomb type friction. The static friction force must be overcome by an applied force before an object can move. The maximum possible friction force between two surfaces before sliding begins is the product of the coefficient of static friction and the normal force: F max = μ s F n {\displaystyle F_{\text{max}}=\mu _{\mathrm {s} }F_{\text{n}}} . When there
5568-545: The locomotive can reach a top speed of 120 km/h (75 mph) (160 km/h (99 mph) optionally) with a starting tractive effort of 519 kN (117,000 lbf). The normal continuous tractive effort is 408 kN (92,000 lbf). The LS 640 reU2 "Turbosplit" transmission allows for a separated traction and wheelslip control of each bogie. This is the first locomotive series equipped with this new technology. Brake equipment consists of electro-pneumatic and engine compression brakes. The smallest drivable curve radius
5655-498: The long course of the development of the law of conservation of energy and of the first law of thermodynamics , friction was recognised as a mode of conversion of mechanical work into heat . In 1798, Benjamin Thompson reported on cannon boring experiments. Arthur Jules Morin (1833) developed the concept of sliding versus rolling friction. In 1842, Julius Robert Mayer frictionally generated heat in paper pulp and measured
5742-435: The most powerful version is the Maxima 40CC with 3,600 kW (4,800 hp) power, intended for freight operators with heavy trains of up to 3,000 metric tons (3,000 long tons; 3,300 short tons). A less powerful version is the Maxima 30CC with 2,750 kW (3,690 hp) power, primarily intended for freight operators with trains of up to 2,500 t (2,500 long tons; 2,800 short tons) or passenger operators. A third version
5829-409: The nature of friction in terms of surface irregularities and the force required to raise the weight pressing the surfaces together. This view was further elaborated by Bernard Forest de Bélidor and Leonhard Euler (1750), who derived the angle of repose of a weight on an inclined plane and first distinguished between static and kinetic friction. John Theophilus Desaguliers (1734) first recognized
5916-512: The new machines. Eight investors including Onghena each contributed 500,000 Belgian francs towards the enterprise; a ninth investor the company Carels Brothers contributed diesel engine manufacturing licenses in exchange for a 5% return of the company's turnover. The name of the new company was Anglo Belgian Company , the Anglo indicating that some of the investment capital was to come from Britain, however World War I intervened and no capital
6003-437: The processes involved is called tribology , and has a history of more than 2000 years. Friction can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start a fire . Another important consequence of many types of friction can be wear , which may lead to performance degradation or damage to components. It is known that frictional energy losses account for about 20% of
6090-408: The role of adhesion in friction. Microscopic forces cause surfaces to stick together; he proposed that friction was the force necessary to tear the adhering surfaces apart. The understanding of friction was further developed by Charles-Augustin de Coulomb (1785). Coulomb investigated the influence of four main factors on friction: the nature of the materials in contact and their surface coatings;
6177-405: The same materials. However, Richard Feynman comments that "with dry metals it is very hard to show any difference." The friction force between two surfaces after sliding begins is the product of the coefficient of kinetic friction and the normal force: F k = μ k F n {\displaystyle F_{k}=\mu _{\mathrm {k} }F_{n}} . This
6264-865: The so-called Painlevé paradoxes , may be encountered with Coulomb friction. Dry friction can induce several types of instabilities in mechanical systems which display a stable behaviour in the absence of friction. These instabilities may be caused by the decrease of the friction force with an increasing velocity of sliding, by material expansion due to heat generation during friction (the thermo-elastic instabilities), or by pure dynamic effects of sliding of two elastic materials (the Adams–Martins instabilities). The latter were originally discovered in 1995 by George G. Adams and João Arménio Correia Martins for smooth surfaces and were later found in periodic rough surfaces. In particular, friction-related dynamical instabilities are thought to be responsible for brake squeal and
6351-435: The temperature rise. In 1845, Joule published a paper entitled The Mechanical Equivalent of Heat , in which he specified a numerical value for the amount of mechanical work required to "produce a unit of heat", based on the friction of an electric current passing through a resistor, and on the friction of a paddle wheel rotating in a vat of water. Osborne Reynolds (1866) derived the equation of viscous flow. This completed
6438-456: The tentative assumption was correct, and it is the actual frictional force. Otherwise, the friction force must be set equal to F f = μ N {\displaystyle F_{f}=\mu N} , and then the resulting force imbalance would then determine the acceleration associated with slipping. The coefficient of friction (COF), often symbolized by the Greek letter μ ,
6525-428: The total energy expenditure of the world. As briefly discussed later, there are many different contributors to the retarding force in friction, ranging from asperity deformation to the generation of charges and changes in local structure . Friction is not itself a fundamental force , it is a non-conservative force – work done against friction is path dependent. In the presence of friction, some mechanical energy
6612-416: The train driver and one for a relief driver or supervisor) and have a standardised and ergonomical control desk. The cabins also have air conditioning and are equipped with all modern needs of today's operating conditions. Powered by either an 16VDZC or 12VDZC engine by Belgian engine manufacturer Anglo-Belgian Corporation , rated at 2,750 kW (3,690 hp) to 3,600 kW (4,800 hp) respectively,
6699-417: The two coefficients are equal, such as teflon-on-teflon. Most dry materials in combination have friction coefficient values between 0.3 and 0.6. Values outside this range are rarer, but teflon , for example, can have a coefficient as low as 0.04. A value of zero would mean no friction at all, an elusive property. Rubber in contact with other surfaces can yield friction coefficients from 1 to 2. Occasionally it
6786-402: The value F f = μ N {\displaystyle F_{f}=\mu N} . Until then, friction is whatever it needs to be to provide equilibrium, so it can be treated as simply a reaction. If the object is on a tilted surface such as an inclined plane, the normal force from gravity is smaller than m g {\displaystyle mg} , because less of
6873-409: The world, rated at 3,600 kW (4,800 hp)). In 2008 a third model, the four-axle Maxima 20 BB, was added to the range. In January 2010, Czech company Lostr (after September 2010 renamed Legios) signed an agreement to manufacture under license the Voith Maxima locomotives. The Czech built locomotives were marketed as Legios General . Voith had supplied components to the railway industry since
6960-471: Was a result of development work by Voith for the "R3000" locomotive's transmission. The 'Turbo Split' LS 640 transmission was first exhibited at Innotrans in 2004 - a key feature of the new transmission was the ability to separately control two outputs from the input - enabling wheelslip control per bogie. In 2005, Vossloh acquired Alstom 's Meinfesa plant (Valencia, Spain), and with it a license to manufacturer GM-EMD based diesel electric locomotives - as
7047-466: Was a success, as was its association with Ogepar . Despite the collapse of the Belgian shipbuilding industry, new markets were found, including overseas power plants. In 1997, a V-formed version of the DZC engine was developed, and the power range of the DZC series was extended to 5,000 hp (3,700 kW) The newly designed VDZC engine met all expectations, and it contributed to the organic growth of
7134-412: Was already drawn by Johann Andreas von Segner in 1758. The effect of the time of repose was explained by Pieter van Musschenbroek (1762) by considering the surfaces of fibrous materials, with fibers meshing together, which takes a finite time in which the friction increases. John Leslie (1766–1832) noted a weakness in the views of Amontons and Coulomb: If friction arises from a weight being drawn up
7221-525: Was expected to be a competitor for a 200 locomotive order from Deutsche Bahn for diesel locomotives for passenger and freight services to replace the " DB V 160 family " of locomotives; in 2011 the Deutsche Bahn AG order was won by Bombardier Transportation with a new multi-engine type of its TRAXX platform. After the exhibition of the demonstrator locomotive at the InnoTrans 2006 fair, it
7308-472: Was initiated in order to produce hydrogen internal combustion engines with a power output of between 0,8 and 2,8 MW. Besides producing dual-fuel engines, the joint venture is also working on a monofuel hydrogen engine. After a COVID year, where the factory managed to stay open and maintain production, ABC introduced the new EVOLVE engine range at the 2021 Europort show in Rotterdam, Holland. As of 2019,
7395-609: Was tested in the first and second quarter of 2008 in the Netherlands, and in Belgium in the fourth quarter. After Dutch and Belgian certification, the locomotive will be passed on to HGK for testing. A third and last demonstrator locomotive is being built and will be used to obtain certification in Poland, Sweden and Norway. As of 2008, 32 locomotives have been ordered, with options for a further 29: The locomotive's body consists entirely of steel. Both cabins have two seats (one for
7482-463: Was tested on several German main lines to receive German certification. It was also tested on the Velim test ring and also went to Norway and Sweden for thermal testing. Final German certification was granted on 23 December 2008 by the German rail authority EBA. A second demonstrator locomotive was built and equipped with Dutch and Belgian safety systems for obtaining Dutch and Belgian certification. It
7569-560: Was to come from England, but the name was kept. Initial production included engines ranging from 6 to 40 horsepower . After the end of the First World War (during which the factory had been occupied and its machines taken to Germany), the company began normal production again. The company survived the Great Depression due to the relatively stable nature of its customer base, the fishing and shipping industries. Later in
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